An experimental insight of friction stir welding of dissimilar AA 6061/Mg AZ 31 B joints

In the present scenario, aerospace and automobile industries depend on lightweight materials such as magnesium and aluminum alloys because of their great balance between mechanical properties and weight ratio. Despite these benefits during the joining process of these dissimilar materials by welding, many challenges arises. The prominent one is related to the low melting points of these lightweight metals which make it almost impossible the joining using conventional arc welding techniques. To tackle this challenge, Friction Stir Welding (FSW) can be considered as a promising candidate tool. In this study, to demonstrate the FSW performances of joining two dissimilar materials we have investigated the joining of AA 6061 and Mg AZ 31 B using a built-in house a modified milling machine. The dissimilar combinations of AA 6061 and Mg AZ 31 B joints were successfully joined by embedding different welding conditions and varying the offset distance. The mechanical performances were evaluated by conducting specific mechanical tests such as micro-hardness, tensile, and impact tests, respectively. To explain the mechanical results, we have applied optical microscopy observation on the microstructure associated with the bonding location. The results prove that the strength of the Friction Stir Welded joints is much higher as compared to other techniques especially in terms of dissimilar metals

Effect of stacking sequence of fibre metal laminates with carbon fibre reinforced composites on mechanical attributes : numerical simulations and experimental validation

Fibre Metal Laminates are structures used primarily in aerospace applications because of their principal advantages such as high strength, lower density, and impact resistance. In the present work, a systematic assessment has been made to evaluate two different stacking sequences of FMLs (Type – I (AA 6061/Carbon Fibre/AA 6061/Carbon Fibre/AA 6061), and Type – II (Carbon Fibre/AA 6061/Carbon Fibre/AA 6061/Carbon Fibre)) against a pure carbon composite (Type - III) as baseline for improvement. The investigations are made for enhanced impact resistance, improved tensile strength, increased flexural capability, microstructural evolution, and surface composition. Mechanical-based testing resulted that Type – I shows significant performance followed by Type – II. The maximum values of tensile strength, impact test, and ultimate load bearing capacity of during flexural test were around 192.92 MPa, 9.3 J, and 155 N, respectively. Correlations of experimental results were drawn against numerical simulation to validate the tensile and flexural results. Microstructural evolution indicated good bonding capability of Type – I FML with the carbon fibre. EDX analysis was carried out analyse surface chemistry. Selected Fibre Metal Laminate sequence can help in improving aeronautical industry's structural applications because of good ductile properties together with fatigue strength and impact resistance